Indicator assembly with halo-free pointer

ABSTRACT

An indicator assembly with a dial face, a pointer and a lamp. The dial face has an opaque portion and defines a shaft aperture. The pointer has a connecting portion, a pointer portion and an opaque boot portion. The connecting portion is disposed in-line with the aperture. The pointer portion is coupled to and extends radially outwardly from the connecting portion. The boot portion extends about the connecting portion and contacts the dial face in a zone that encircles the aperture. The lamp is disposed rearwardly of the dial face and provides a source of light. A method for reducing or eliminating a halo effect is also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/029,961, which was filed on Jan. 5, 2005 now U.S. Pat. No.6,983,717.

INTRODUCTION

The present invention generally relates to illuminated indicatorassemblies and more particularly to an illuminated indicator assemblywherein light leakage about the hub of a pointer is significantlyreduced or eliminated altogether.

Illuminated indicator assemblies having a rotating pointer are known inthe art. In such instruments, the pointer is driven by a shaft thatextends through a hole in a display face or member. One drawback of theknown illuminated indicator assembly arrangements concerns light leakagethrough the hole in the display face. More specifically, light leakingthrough the hole in the display face tends to illuminate the hub of thepointer which is known in the art as producing a “halo effect”.

The halo effect is particularly problematic with non-black dial facesand in particular, dial faces with background colors that are relativelylight in color such as white, cream or tan. Accordingly, it would bedesirable to have an illuminated indicator assembly that significantlyreduced or eliminated light leakage about the pointer.

SUMMARY

In one form, the present teachings provide an indicator assembly with adial face, a pointer and a lamp. The dial face has an opaque portion anddefines a shaft aperture. The pointer has a connecting portion, apointer portion and an opaque boot portion. The connecting portion isdisposed in-line with the aperture. The pointer portion is coupled toand extends radially outwardly from the connecting portion. The bootportion extends about the connecting portion and contacts the dial facein a zone that encircles the aperture. The lamp is disposed rearwardlyof the dial face and provides a source of light.

In another form, the present teachings provide an indicator assemblywith a display face, a pointer shaft, a pointer and a lamp. The displayface includes an opaque portion with a shaft aperture formedtherethrough. The pointer shaft extends through the shaft aperture. Thepointer has a hub portion, a pointer portion and a boot portion. The hubportion is coupled to the pointer shaft and is disposed on a first sideof the display face. The pointer portion extends radially outwardly hubportion. The boot portion is formed of an opaque material and is coupledto the hub portion so as to contact the first side of the display facein a zone that encircles the shaft aperture. The lamp is disposedrearwardly of the display face and provides a source of light

In yet another form, the present teachings provide a method for reducingor eliminating a halo effect. The method includes: providing a displayface having an opaque portion with a shaft aperture formed therethrough;providing a pointer with a hub portion and a boot portion, the bootportion being coupled to the hub portion and being formed of an opaquematerial; aligning a pointer to the shaft aperture such that the bootportion contacts the display face in a zone encircling the shaftaperture; and illuminating a lamp on a side of the display face oppositethe boot portion.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional advantages and features of the present invention will becomeapparent from the subsequent description and the appended claims, takenin conjunction with the accompanying drawings, wherein:

FIG. 1 is a front view of an automotive indicator assembly constructedin accordance with the teachings of the present invention;

FIG. 2 is a sectional view of the indicator assembly of FIG. 1 takenalong a longitudinal axis of the pointer;

FIG. 3 is a sectional view similar to that of FIG. 2 but illustrating aportion of a second automotive indicator assembly constructed inaccordance with the teachings of the present invention; and

FIG. 4 is a sectional view similar to that of FIG. 2 but illustrating aportion of a third automotive indicator assembly constructed inaccordance with the teachings of the present invention.

DETAILED DESCRIPTION OF THE VARIOUS EMBODIMENTS

With reference to FIGS. 1 and 2 of the drawings, an indicator assemblyconstructed in accordance with the teachings of the present invention isgenerally indicated by reference numeral 10. The indicator assembly 10can generally include a dial 20, a drive unit 22, a pointer 24 and alamp 26. While the indicator assembly 10 is illustrated as being aspeedometer, it will be appreciated that the teachings of the presentinvention have applicability to various other types of instruments,whether automotive or not, and as such, the particular exampleillustrated is not intended to be limiting in any way.

The dial 20 can include a dial face 30 with an opaque portion orbackground 32 and dial face indicia 34, which may be translucent. Thebackground 32 can have any coloration, including a non-black color suchas white, cream, tan or another relatively light color. A shaft aperture36 can be formed through the background 32.

The drive unit 22 can include a motor, such as a stepper motor, and maybe mounted in a manner that is conventional and well known in the art,such as to a printed circuit board 40. The drive unit 22 is mountedrearwardly of the dial face 30 and includes a rotatable output shaft 42that is disposed in-line with the shaft aperture 36. While the outputshaft 42 is illustrated as extending forwardly of a forward surface 44of the dial face 30, it will be appreciated that the output shaft 42 maybe formed otherwise depending upon the configuration of the pointer 24.

The pointer 24 can include a connection portion 50, a pointer portion 52and an opaque boot portion 54. The connection portion 50 can include ahub 56 and a cover 58. The hub 56 can extend through the shaft aperture36 in the dial face 30 and can be coupled for rotation with the outputshaft 42. The hub 56 can include one or more light transmitting windows62 that will be discussed in greater detail, below. The cover 58 can bea discrete component that can be formed of an opaque material andfixedly coupled to the hub 56 in a suitable process, such as bonding orheat staking.

The pointer portion 52 is can be coupled to the hub 56 to thereby rotatetherewith and can be formed of a transparent or translucent material.The pointer portion 52 can extend radially outwardly from the hub 56 andcan terminate proximate the dial face indicia 34.

The boot portion 54 can be formed of a resilient opaque material, suchas an elastomer or a thermoplastic elastomer. It will be appreciatedthat any opaque material that is soft, resilient and/or relatively slickcould be employed to fabricate the boot portion 54 in whole or in part.Further suitable materials include textiles, which may be naturalmaterials such as silk, felt or cotton or man-made fabrics or threadssuch as polyester; bristles (e.g., soft nylon, natural hair); andmaterials such as polytetrafluoroethylene (PTFE) and perfluoroalkoxypolymer resin (PFA). FIG. 3 illustrates an embodiment wherein the bootportion 54 a is partially formed of a textile 54 a-1 and FIG. 4illustrates an embodiment wherein the boot portion 54 b is partiallyformed of bristles 54 b-1. Returning to FIGS. 1 and 2, the boot portion54 can be a discrete component that is coupled to the connection portion50 or can be formed onto the connection portion 50 in a suitableprocess, such as overmolding. The boot portion 54 can include an edge orlip 64 that contacts the dial face 30 in a zone 66 that is disposedabout the shaft aperture 36 in the dial face 30.

The lamp 26 can include one or more incandescent lamps or LEDs that maybe mounted in a manner that is conventional and well known in the art,such as to the printed circuit board 40. The lamp 26 can be configuredto illuminate the dial face indicia 34 and/or the pointer 24 in a mannerthat is well known in the art. Briefly, where the dial face indicia 34is to be illuminated, a light guide (not specifically shown) may beemployed to direct light about a rearward surface of the dial 20 toback-illuminate the dial face indicia 34. As the pointer 24 is to beilluminated in the example provided, light generated by the lamp 26 canbe transmitted through the light transmitting windows 62 of the hub 56and into the pointer portion 52. As the cover 58 is opaque, lighttraveling through the pointer 24 appears to only illuminate the pointerportion 52.

Light generated by the lamp 26 may “leak” through the dial face 30 inthe space between the output shaft 42 and the edge of the shaft aperture36. Significantly, contact between the opaque boot portion 54 and thedial face 30 prevents any light that “leaks” through the dial face 30from being viewed from the front of the indicator assembly 10 andthereby effectively eliminates the above-noted “halo effect”.

While the invention has been described in the specification andillustrated in the drawings with reference to various embodiments, itwill be understood by those skilled in the art that various changes maybe made and equivalents may be substituted for elements thereof withoutdeparting from the scope of the invention as defined in the claims.Furthermore, the mixing and matching of features, elements and/orfunctions between various embodiments is expressly contemplated hereinso that one of ordinary skill in the art would appreciate from thisdisclosure that features, elements and/or functions of one embodimentmay be incorporated into another embodiment as appropriate, unlessdescribed otherwise, above. Moreover, many modifications may be made toadapt a particular situation or material to the teachings of theinvention without departing from the essential scope thereof. Therefore,it is intended that the invention not be limited to the particularembodiment illustrated by the drawings and described in thespecification as the best mode presently contemplated for carrying outthis invention, but that the invention will include any embodimentsfalling within the foregoing description and the appended claims.

1. An indicator assembly comprising: a dial having a dial face, the dialface having an opaque portion with an aperture formed therethrough; apointer with a connecting portion, a pointer portion and an opaque bootportion, the connecting portion being disposed in-line with theaperture, the pointer portion being coupled to and extending radiallyoutwardly from the connecting portion, the boot portion extending aboutthe connecting portion and contacting the dial face in a zone thatencircles the aperture; and a lamp that is disposed rearwardly of thedial face, the lamp providing a source of light; wherein the bootportion is at least partially formed of at least one material selectedfrom a group consisting of textiles, bristles, polytetrafluoroethyleneand perfluoroalkoxy polymer resin.
 2. The indicator assembly of claim 1,wherein the pointer portion is formed of a translucent material and atleast a portion of the light produced by the lamp is received by thepointer portion to illuminate the pointer portion.
 3. The indicatorassembly of claim 1, wherein the dial face has a viewing surface, theviewing surface having a background, the background being a color otherthan black.
 4. An indicator assembly comprising: a display face havingan opaque portion with a shaft aperture formed therethrough; a pointershaft extending through the shaft aperture; a pointer having a hubportion, a pointer portion and a boot portion, the hub portion beingcoupled to the pointer shaft and being disposed on a first side of thedisplay face, the pointer portion extending radially outwardly from thehub portion, the boot portion being formed of an opaque material, theboot portion being coupled to the hub portion and contacting the firstside of the display face in a zone that encircles the shaft aperture;and a lamp that is disposed rearwardly of the display face, the lampproviding a source of light; wherein the boot portion is at leastpartially formed of at least one material selected from a groupconsisting of textiles, bristles, polytetrafluoroethylene andperfluoroalkoxy polymer resin.
 5. The indicator assembly of claim 4,wherein the pointer portion is formed of a translucent material and atleast a portion of the light produced by the lamp is received by thepointer portion to illuminate the pointer portion.
 6. The indicatorassembly of claim 4, wherein the display face has a viewing surface, theviewing surface having a background, the background being a color otherthan black.
 7. A method comprising: providing a display face having anopaque portion with a shaft aperture formed therethrough; providing apointer with a hub portion and a boot portion, the boot portion beingcoupled to the hub portion and being formed of at least one opaquematerial selected from a group consisting of textiles, bristles,polytetrafluoroethylene and perfluoroalkoxy polymer resin; aligning apointer to the shaft aperture such that the boot portion contacts thedisplay face in a zone encircling the shaft aperture; and illuminating alamp on a side of the display face opposite the boot portion.
 8. Themethod of claim 7, wherein illumination of the lamp illuminates aportion of the display face.
 9. The method of claim 8, whereinillumination of the lamp illuminates a portion of the pointer.